For example, as a conventional vehicular AC generator slip ring device, there is known one that is provided with a labyrinth configuration that is not contaminated by salty water, oil, dust, and the like. The slip ring device is a formed product in which a pair of metal rings (conductive rings) in which brushes slide and a pair of connection terminals electrically connected to the rings are molded (for example, see Patent Document 1).
Above all, there is shown one which has means in which a slip ring unit of a configuration in which each of a pair of connected connection elements is axially extended and embedded in an insulation material to be connected to a ring portion of the insulation material is fitted by press-fitting to a shaft of an alternator (for example, Patent Document 2).
Two outward projection portions radially opposite to each other are provided in a protruding condition at symmetrical positions at an angular distance of 90 degrees with respect to the connection member. A slightly recessed concavity is formed on the outer peripheral surface of the projection portion. This is an improvement in which a positioning is reliably performed during automatically fitting and grip and alignment of the slip ring units are further facilitated.